Cisco CallManager
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Image:Cisco-Logo.svg CallManager is a Cisco product. It is formally referred to as Cisco Unified CallManager (note capitalization), or CCM for short.
CallManager tracks all active VoIP network components; these include phones, gateways, conference bridges, transcoding resources, and voicemail boxes among others. CallManager often utilizes the Skinny Client Control Protocol (SCCP) as a communications protocol for signaling the hardware endpoints of the system, such as IP Phones. H.323, Media Gateway Control Protocol (MGCP) or Session Initiation Protocol (SIP) is used to pass call signaling to gateways.
CCM evaluates called numbers and activates gateway events to receive or send calls to the PSTN.
The Cisco CallManager is installed on the Cisco Media Convergence Server (MCS). Typically, multiple (up to eight) MCS are clustered for distributed call processing and fault tolerance.
In (2004) Cisco released Cisco CallManager 4.1. It includes various enhancements such as handling of multiple calls (up to 200) on a single line presence. Additionally, some of the new features of CCM 4.0 include greatly enhanced conference calling features, enhanced Client Matter Code (CMC) and Forced Account Code (FAC), Multilevel Precedence and Preemption (MLPP) and Malicious Call Identification (MCID). CallManager 4.1 also enhances the encryption capabilities first introduced in CallManager 4.0. When using Cisco Phones 7940/7960/7970 or 7971 it is now possible to encrypt signalling as well as voice traffic itself.
CallManager 5.0 and 4.2 were released by Cisco on Monday the 6th of March 2006. At the same time Cisco renamed the product "Cisco Unified CallManager"; they also added the Unified tag to all of their Voice and Video offerings (i.e. Cisco Unified Contact Centre, Cisco Unified MeetingPlace).
Cisco Unified CallManager 5.0 is Linux based and for the first time can use SIP to end-points; apart from the addition of SIP it is feature compatible with CallManager 4.1(3). CallManager 5.0 servers are being sold as pre-installed appliances and non Cisco staff will have very limited access to the OS; CallManager 5.0 can also be installed on non appliance MCS servers. Users of CallManager 4.x can upgrade to CallManager 5.0 and keep their current Databases by having another server on the LAN with a shared drive available during the upgrade process.
Cisco Unified CallManager 4.2 runs on Windows and includes new PABX features over 4.1(3) but it does not include SIP end-point support.
Cisco promise PABX feature compatibility for the Linux based solution with CallManager 5.1. Cisco also keep saying that they are not dropping development for Windows. However it is widely believed in the industry that this is only said to placate Linux phobic CTOs and people who have no immediate plans to upgrade. The reason for the scepticism is that when Cisco are asked if CallManager for Windows will ever go above version 4.x or will support SIP end-points the answer is no. Since some of the new Unified products make heavy use of both SIP and SIMPLE it would be a good assumption to make that by 2008 CallManager for Windows will no longer be an actively sold product.
Callmanager History
The product started its life in 1994 as Multimedia Manager 1.0. The Multimedia Manager product was designed to be the signaling controller for a point-to-point video solution. It was originally developed for a HP-UX platform using the SDL-88 programming language, but was later ported to the Windows NT 3.51 platform. In 1997, it was renamed Selsius-CallManager and changed from a videoconferencing solution to a system designed to route voice calls over an IP network. Selsius was acquired by Cisco in 1998 and the current product is a build up of the 1997 port.